[1] Ctr Dis Control & Prevent, Natl Ctr Birth Defects & Dev Disabil, Atlanta, GA 30333 USA
[2] Childrens Hosp & Reg Med Ctr, Div Pulm Med, Seattle, WA USA
[3] Univ Wisconsin, Coll Agr & Life Sci, Dept Nutr Sci, Madison, WI 53706 USA
[4] Univ Wisconsin, Sch Med, Dept Biostat & Med Informat, Madison, WI 53706 USA
[5] Univ Wisconsin, Sch Med, Dept Pediat, Madison, WI 53706 USA